<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Hello React!</title>
<script src="https://cdn.staticfile.net/react/16.4.0/umd/react.development.js"></script>
<script src="https://cdn.staticfile.net/react-dom/16.4.0/umd/react-dom.development.js"></script>
<script src="https://cdn.staticfile.net/babel-standalone/6.26.0/babel.min.js"></script>
</head>
<body>

<div id="example"></div>
<script type="text/babel">
class Clock extends React.Component {
  render() {
    return (
      <div>
        <h1>Hello, world!</h1>
        <h2>现在是 {this.props.date.toLocaleTimeString()}.</h2>
      </div>
    );
  }
}

function tick() {
  ReactDOM.render(
    <Clock date={new Date()} />,
    document.getElementById('example')
  );
}

setInterval(tick, 1);
</script>

</body>
</html>